The third legal case in as many weeks has been brought against beleaguered opposition leader Sam Rainsy, who remains in self-imposed exile in France.

Phnom Penh Municipal Court deputy prosecutor Vong Bunvisoth on Tuesday ordered Rainsy to appear for questioning on January 4 over accusations he defamed National Assembly President Heng Samrin in a November 17 Facebook post.

The fresh summons, based on a request by Samrin lawyer Ky Tech, follows an order on November 13 for Rainsy to serve a two-year prison term for defaming Foreign Minister Hor Namhong in 2008 and another summons, issued November 20, linking the CNRP president to the case of imprisoned opposition Senator Hong Sok Hour.

Yesterday, Tech said Rainsy’s post defamed his client by alleging that the Vietnam-backed government led by Samrin that toppled the Pol Pot regime in 1979 had staged a tribunal that accused the late King Father Norodom Sihanouk, an erstwhile ally of the Khmer Rouge, of being a traitor and sentenced him to death.

Tech said Rainsy’s post was wrong and that Samrin’s government, the People’s Republic of Kampuchea (PRK), had merely invited Sihanouk to return home.

“Instructing me, Samdech [Samrin] confirmed clearly that there was no trial or sentence for [Sihanouk] at any time,” Tech said.

“This accusation twists [the facts] and puts the fault on [Samrin]. [Samrin] was a top leader of the country at the time, so [Samrin] must sue, otherwise Khmer, national and international citizens will have a misunderstanding about [Samrin].”

In a clip included in Rainsy’s post, Sihanouk, in exile at the time, can be seen rallying against Vietnam’s military support of the PRK.

“The yuon has sent many soldiers to work for Heng Samrin,” Sihanouk says, using a word for the Vietnamese considered derogatory by some.

Responding yesterday, Rainsy said there were no grounds for the claim as it was Sihanouk, not he, who had mentioned Sarmin in the clip, which, he added, was filmed around 1983.

“I just referred to ‘the regime born on 7 January 1979’, without mentioning any name in my comment,” Rainsy said via email.

Rainsy uploaded the post the day after he was stripped of his lawmaker status by the assembly’s permanent committee, which is chaired by Samrin, who is also a senior official and honorary president of the ruling Cambodian People’s Party.

Rainsy on trial: view an interactive timeline of the opposition leader's ongoing legal battles

The permanent committee claimed Rainsy could not continue to serve as a lawmaker as he was considered a criminal after Namhong’s lawyer requested the enforcement of the 2011 defamation conviction for statements alleging the foreign minister was responsible for deaths at a Khmer Rouge prison camp.

Abroad when that warrant was issued, Rainsy, despite an initial pledge to return, opted for self-imposed exile in Europe, as in 2009 and 2005, when he also faced prison on charges widely considered politically motivated.

The CNRP, human rights groups and members of the international community, including the European Parliament, have decried the moves as part of a broader pattern of political persecution by the CPP against the opposition.

Included in the recent crackdown, say critics, is the CPP’s ousting of CNRP deputy Kem Sokha as parliament’s first vice president and the bashing of two opposition lawmakers outside parliament by a group of pro-CPP protesters on October 26.

In a statement yesterday, the Ministry of Foreign Affairs, responding to criticism by Malaysian MP and ASEAN Parliamentarians for Human Rights member Charles Santiago, offered a point-by-point explanation “in light of certain misleading dissemination of [the] recent political situation in Cambodia”.

The ministry stressed the gang attack on CNRP lawmakers Nhay Chamroeun and Kong Sakphea, who suffered serious injuries requiring surgery, occurred more than an hour after the majority of protesters calling for Sokha’s removal as the parliament’s first vice president had dispersed.

Further, in an apparent attempt to justify the actions of attackers, who ripped the victims from their cars and repeatedly kicked them in street, the statement says Chamroeun and Sakpea “reportedly threw derogatory remarks at some of the remaining protesters”.

“Outraged by this offending behaviour, those protesters blocked the deputies’ cars and started beating the parliamentarians,” reads the statement, which also points to the arrest of three suspects, all soldiers, and the government’s condemnation of the violence.

Yesterday, Chamroeun vehemently denied this claim.

“It is ridiculous, they falsify the facts and misrepresent reality . . . why? Because those who attacked me are pro-government, that’s why.”

The Foreign Ministry also reiterated arguments used to defend stripping Rainsy’s lawmaker status and Sokha’s ousting as assembly vice president, claiming both were lawful and warranted.

CNRP spokesman Yim Sovann said the party had stopped “paying attention” to the CPP’s “campaign of suppression”.